# -*- coding: utf-8 -*-

import xml.etree.ElementTree as ET
tree = ET.parse("xmltest.xml")
root = tree.getroot()
#修改
for node in root.iter('year'):
    new_year = int(node.text) + 1
    node.text = str(new_year)
    node.set("updated","yes")
tree.write("xmltest.xml")
#删除node
for country in root.findall('country'):
   rank = int(country.find('rank').text)
   if rank > 50:
     root.remove(country)
tree.write('output.xml')